Separate agg-authored code from fx-authored code.
[pdfium.git] / third_party / agg23 / agg_vcgen_dash.cpp
1
2 //----------------------------------------------------------------------------
3 // Anti-Grain Geometry - Version 2.3
4 // Copyright (C) 2002-2005 Maxim Shemanarev (http://www.antigrain.com)
5 //
6 // Permission to copy, use, modify, sell and distribute this software
7 // is granted provided this copyright notice appears in all copies.
8 // This software is provided "as is" without express or implied
9 // warranty, and with no claim as to its suitability for any purpose.
10 //
11 //----------------------------------------------------------------------------
12 // Contact: mcseem@antigrain.com
13 //          mcseemagg@yahoo.com
14 //          http://www.antigrain.com
15 //----------------------------------------------------------------------------
16 //
17 // Line dash generator
18 //
19 //----------------------------------------------------------------------------
20 #include "../../core/include/fxcrt/fx_basic.h"
21 #include "agg_vcgen_dash.h"
22 #include "agg_shorten_path.h"
23 namespace agg
24 {
25 vcgen_dash::vcgen_dash() :
26     m_total_dash_len(0),
27     m_num_dashes(0),
28     m_dash_start(0),
29     m_shorten(0),
30     m_curr_dash_start(0),
31     m_curr_dash(0),
32     m_src_vertices(),
33     m_closed(0),
34     m_status(initial),
35     m_src_vertex(0)
36 {
37 }
38 void vcgen_dash::remove_all_dashes()
39 {
40     m_total_dash_len = 0;
41     m_num_dashes = 0;
42     m_curr_dash_start = 0;
43     m_curr_dash = 0;
44 }
45 void vcgen_dash::add_dash(FX_FLOAT dash_len, FX_FLOAT gap_len)
46 {
47     if(m_num_dashes < max_dashes) {
48         m_total_dash_len += dash_len + gap_len;
49         m_dashes[m_num_dashes++] = dash_len;
50         m_dashes[m_num_dashes++] = gap_len;
51     }
52 }
53 void vcgen_dash::dash_start(FX_FLOAT ds)
54 {
55     m_dash_start = ds;
56     calc_dash_start(FXSYS_fabs(ds));
57 }
58 void vcgen_dash::calc_dash_start(FX_FLOAT ds)
59 {
60     m_curr_dash = 0;
61     m_curr_dash_start = 0;
62     while(ds > 0) {
63         if(ds > m_dashes[m_curr_dash]) {
64             ds -= m_dashes[m_curr_dash];
65             ++m_curr_dash;
66             m_curr_dash_start = 0;
67             if(m_curr_dash >= m_num_dashes) {
68                 m_curr_dash = 0;
69             }
70         } else {
71             m_curr_dash_start = ds;
72             ds = 0;
73         }
74     }
75 }
76 void vcgen_dash::remove_all()
77 {
78     m_status = initial;
79     m_src_vertices.remove_all();
80     m_closed = 0;
81 }
82 void vcgen_dash::add_vertex(FX_FLOAT x, FX_FLOAT y, unsigned cmd)
83 {
84     m_status = initial;
85     if(is_move_to(cmd)) {
86         m_src_vertices.modify_last(vertex_dist(x, y));
87     } else {
88         if(is_vertex(cmd)) {
89             m_src_vertices.add(vertex_dist(x, y));
90         } else {
91             m_closed = get_close_flag(cmd);
92         }
93     }
94 }
95 void vcgen_dash::rewind(unsigned)
96 {
97     if(m_status == initial) {
98         m_src_vertices.close(m_closed != 0);
99         shorten_path(m_src_vertices, m_shorten, m_closed);
100     }
101     m_status = ready;
102     m_src_vertex = 0;
103 }
104 unsigned vcgen_dash::vertex(FX_FLOAT* x, FX_FLOAT* y)
105 {
106     unsigned cmd = path_cmd_move_to;
107     while(!is_stop(cmd)) {
108         switch(m_status) {
109             case initial:
110                 rewind(0);
111             case ready:
112                 if(m_num_dashes < 2 || m_src_vertices.size() < 2) {
113                     cmd = path_cmd_stop;
114                     break;
115                 }
116                 m_status = polyline;
117                 m_src_vertex = 1;
118                 m_v1 = &m_src_vertices[0];
119                 m_v2 = &m_src_vertices[1];
120                 m_curr_rest = m_v1->dist;
121                 *x = m_v1->x;
122                 *y = m_v1->y;
123                 if(m_dash_start >= 0) {
124                     calc_dash_start(m_dash_start);
125                 }
126                 return path_cmd_move_to;
127             case polyline: {
128                     FX_FLOAT dash_rest = m_dashes[m_curr_dash] - m_curr_dash_start;
129                     unsigned cmd = (m_curr_dash & 1) ?
130                                    path_cmd_move_to :
131                                    path_cmd_line_to;
132                     if(m_curr_rest > dash_rest) {
133                         m_curr_rest -= dash_rest;
134                         ++m_curr_dash;
135                         if(m_curr_dash >= m_num_dashes) {
136                             m_curr_dash = 0;
137                         }
138                         m_curr_dash_start = 0;
139                         *x = m_v2->x - (m_v2->x - m_v1->x) * m_curr_rest / m_v1->dist;
140                         *y = m_v2->y - (m_v2->y - m_v1->y) * m_curr_rest / m_v1->dist;
141                     } else {
142                         m_curr_dash_start += m_curr_rest;
143                         *x = m_v2->x;
144                         *y = m_v2->y;
145                         ++m_src_vertex;
146                         m_v1 = m_v2;
147                         m_curr_rest = m_v1->dist;
148                         if(m_closed) {
149                             if(m_src_vertex > m_src_vertices.size()) {
150                                 m_status = stop;
151                             } else {
152                                 m_v2 = &m_src_vertices
153                                        [
154                                            (m_src_vertex >= m_src_vertices.size()) ? 0 :
155                                            m_src_vertex
156                                        ];
157                             }
158                         } else {
159                             if(m_src_vertex >= m_src_vertices.size()) {
160                                 m_status = stop;
161                             } else {
162                                 m_v2 = &m_src_vertices[m_src_vertex];
163                             }
164                         }
165                     }
166                     return cmd;
167                 }
168                 break;
169             case stop:
170                 cmd = path_cmd_stop;
171                 break;
172         }
173     }
174     return path_cmd_stop;
175 }
176 }